Prosthetic device utilizing electric vacuum pump

ABSTRACT

Evacuation devices for evacuating the socket of a prosthetic limb, and prosthetic limb systems employing such vacuum devices. The evacuation devices each preferably include at least an electrically powered vacuum pump and a power source. Such evacuation devices can be attached at various locations on or in a prosthetic limb. Because the electrically powered pump does not require manual manipulation to create vacuum, it is substantially easier to use than a manual pump. Due to the small size and small power source required by such an electrically powered pump, an evacuation device may be readily incorporated into a prosthesis.

The present application is a continuation-in-part of U.S. patentapplication Ser. No. 11/149,858, filed on Jun. 10, 2005.

BACKGROUND OF THE INVENTION

The present invention is directed to electrically-powered evacuationdevices for use in evacuating a prosthetic socket and/or to prostheticlimbs incorporating such electrically-powered evacuation devices. Thepresent invention is also directed to various systems and methods formonitoring, performing, and controlling such devices.

Artificial limbs have been in use throughout history, having been firstrecorded circa 2750 B.C. During that period of time, interfacing andsuspending an artificial limb has been a continuing challenge. Variousand numerous theories and anatomical constructs have been used over timein an evolving manner, and these have revealed a number of key factorsin maximizing comfort and functional potential for persons who wearartificial limbs.

Firstly, the surgical procedure used to perform limb amputation is animportant factor. The size and shaping of the patient's residual limb isoften important to the comfort the patient will later have with aprosthesis. Stated simply, it is critical that the residual limb andprosthesis interface tightly and couple and distribute pressure evenlyacross the surface of the residual limb.

Early versions of artificial limbs required the use of leather orequivalent straps or belts to suspend the artificial limb upon theperson. Later systems employed linkage techniques such as condylarwedges, rubber or synthetic elastic tubing, thermoplastic roll-onsleeves with pin locking systems, and sub-atmospheric pressure. Ofthese, sub atmospheric pressure is typically often preferred, because itcreates a linkage that provides maximum proprioceptive feedback andcontrol for the artificial limb user. It also provides the best linkagebetween the user's limb and the prosthetic device.

Creating a reliable sub atmospheric pressure chamber between theresidual limb and prosthetic device has, however, proved to be achallenge. As new airtight thermoplastic and thermo set materials haveevolved, along with airtight thermoplastic roll-on liners, the potentialfor creating a sub-atmospheric pressure within the prosthetic chamber(socket) has improved. Specifically, the patient's residual limb iscovered with a roll-on urethane or other thermoplastic liner, whichhelps to protect the user's tissue from unwanted isolated high negativepressure values, and provides cushioning for the tissue at the sametime. The liner also helps to distribute the sub-atmospheric pressureapplied to the user's limb in a more uniform manner.

Several mechanical means for creating an elevated negative pressurechamber within a prosthetic socket have emerged. One method disclosed inU.S. Pat. No. 6,554,868, utilizes a weight activated pump, in which subatmospheric pressure is maintained strategically within the socket asthe user walks. Under this approach, vacuum is maintained as the patientambulates with the artificial limb.

This method of evacuating a prosthetic socket has several disadvantages,however. First, the weight activated pump is heavy, and cannot beremoved even in the case of a pump failure. The weight activated pumpalso requires a certain minimum space between the user's limb andprosthetic foot, which may be more than is available if the patient hasa relatively long residual limb. This prohibits the use of thistechnology for many artificial limb users. Further, a weight-activatedpump system requires some number of weight activated strokes beforebecoming effective.

Another evacuation method disclosed in the above-referenced patent usesa hand-held sub-atmospheric pressure pump, much like that used to bleedbrake systems on an automobile. This method provides for acceptablesocket evacuation, but requires the individual to carry the hand-heldpump upon their person for use in case of vacuum failure. The hand-heldpump is also awkward for many individuals to use and requires a certainamount of dexterity and strength to operate. This is a common problemfor elderly individuals.

As can be understood from the foregoing discussion, known mechanicalsystems for evacuating a prosthetic socket have several disadvantages.Aside from those specific disadvantages detailed above, such mechanicalsystems are further burdened with other general problems. Primarily, theevacuation pump associated with such systems is active only when theuser is ambulating, and then is activated with every step—regardless ofthe wishes of the user.

Therefore, one general disadvantage to such a mechanical systems is thatthe pump is unable to draw vacuum when the user is sedentary. This meansthat absent the carrying and use of a separate hand-held pump, there isno way to properly don an associated prosthesis without standing up andwalking on the prosthesis in a partially donned (i.e., non-evacuated)state. Similarly, if the socket loses pressure while the user is sittingor otherwise non-ambulatory, there is no way (aside from a separatehand-held pump) to re-evacuate the socket other than walking or bouncingon the now improperly suspended prosthesis.

Yet another disadvantage to such mechanical evacuation systems is that aweight-activated pump will always eventually evacuate the prostheticsocket to some predetermined level. As such, there is no way for a userto adjust the level of vacuum to coincide with a particular activity orcomfort level. For example, a user would not be able to increase thevacuum level over some typical vacuum level during a period of increasedactivity, nor decrease the vacuum level to compensate for a particularlysore or sensitive residual limb.

Thus, there is a need for improved means of achieving sub-atmosphericpressure within a prosthetic socket. The present invention satisfiesthis need.

SUMMARY OF THE INVENTION

The present invention overcomes the disadvantages inherent to knownprosthetic socket evacuation devices using mechanical (e.g.,weight-activated) pumps. Rather, the present invention is directed tosocket evacuation device employing an electrically-activated pump.Because the electrically-activated pump does not require manualmanipulation to create vacuum, it is substantially easier to use than amanual pump. Further, due to the compact size and minimal powerconsumption associated with an evacuation device of the presentinvention, it may be readily incorporated into/onto a prosthesis.

A device of the present invention thus affords substantial generaladvantages over the manual pumps and gait-driven pumps of the prior art,and the inventors are believed to be the first to present a practicalapproach to providing an electrically evacuated prosthetic device. The'868 patent referenced above suggests the inclusion of a genericallydrawn “vacuum source” and “power source”, and a regulator for automaticvacuum maintenance, into an outer socket of a prosthesis (see, e.g.,FIGS. 7 and 9 and discuss thereof); however, there is no specificreference therein to a vacuum source or power source that is of suitablesize and weight for such an application, as is provided by the inventorshereof. The present invention thus represents an advance and an enabledapproach to providing an electrically actuated, portable vacuum pump ina prosthesis.

An electrically-activated evacuation device of the present inventionoffers additional advantages not possible with a manual or gait-drivendevice. For example, in addition to embodiments wherein the vacuum levelis directly controlled by the user, the present invention may alsopossess semi-automatic or automatic vacuum level control and/orsemi-automatic or automatic vacuum regulation.

The above and other objects and advantages of the present inventionshall be made apparent from the accompanying drawings and thedescription thereof.

BRIEF DESCRIPTION OF THE DRAWINGS

In addition to the features mentioned above, other aspects of thepresent invention will be readily apparent from the followingdescriptions of the drawings and exemplary embodiments, wherein likereference numerals across the several views refer to identical orequivalent features, and wherein:

FIG. 1 illustrates a prosthetic limb incorporating an electric vacuumpump according to one embodiment of the present invention;

FIG. 2 is a disassembled view of the prosthetic limb of FIG. 1,illustrating internal components thereof;

FIG. 3 is a cutaway view of the prosthetic limb of FIG. 1 showing theinternal components as positioned when the limb is in use;

FIGS. 4A and 4B are cutaway views of the prosthetic limb of FIG. 1showing its use in creating vacuum engagement of a limb with a socket;

FIG. 5 illustrates another embodiment of the present invention, in whichthe electric pump and power source are housed in a separate portableevacuation device;

FIG. 6 depicts another embodiment of the present invention, wherein theelectric pump and power source are placed into a sleeve that issubsequently installed into a pylon;

FIG. 7 illustrates a prosthetic limb employing another embodiment of thepresent invention, wherein an evacuation device includes a vacuum pumpand power source that are located within a housing designed forattachment to a universal distal adapter that is built into the distalend of a prosthetic socket;

FIG. 8 is a plan view into the socket of the prosthetic limb of FIG. 7,wherein a portion of the universal distal adapter and a portion of thehousing are visible;

FIG. 9 is a section view of a portion of the prosthetic limb of FIG. 7,taken along line C-C of FIG. 8;

FIG. 10A is an enlarged view of the detailed area called out in FIG. 9;

FIG. 10B is a bottom plan view of the universal distal adapter;

FIG. 11 is a section view of a portion of the prosthetic limb of FIG. 7,taken along line D-D of FIG. 8;

FIG. 12 is an enlarged view of the detailed area called out in FIG. 11;

FIG. 13 depicts another embodiment of the present invention, wherein anevacuation device includes a vacuum pump and power source located withina housing that is mounted around the pylon of a prosthetic limb;

FIG. 14A shows another embodiment of the present invention, wherein anevacuation device includes a vacuum pump and power source located in ahousing that is attached to an adapter integrated into a side wall of aprosthetic socket;

FIG. 14B shows another embodiment of the present invention, wherein anevacuation device includes a vacuum pump and power source located in achamber that is integral to and protrudes from the side wall of aprosthetic socket;

FIG. 15 illustrates another embodiment of the present invention, whereinan evacuation device includes a vacuum pump and power source located ina housing that is positioned within an exoskeletal prosthetic device;

FIG. 16 depicts another embodiment of the present invention, wherein anevacuation device includes a vacuum pump and power source located in ahousing that is affixed to a mounting plate designed to be mountedbetween adjacent components of a prosthetic limb;

FIG. 17 shows another embodiment of the present invention wherein anevacuation device includes a vacuum pump and power source located in aprosthetic foot or within a housing that is positioned in a prostheticfoot;

FIG. 18 illustrates another embodiment of the present invention, whereinan evacuation device includes a vacuum pump and power source locatedwithin a housing that is located on the user's person and provided toevacuate the socket of a prosthetic limb;

FIG. 19 depicts yet another embodiment of the present invention, whereina manifold connects a vacuum source to the interior of a prostheticsocket; and

FIG. 20 shows a magnetic switch that can be used to initiate theenergizing of a vacuum pump in any embodiment of the present invention.

DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENT(S)

FIG. 1 illustrates one embodiment of a prosthesis 10 in accordance withprinciples of the present invention. The prosthesis includes a socket 12for receiving an amputee's residual limb, a column (pylon) 14, which istypically a cylindrical section of lightweight metal such as aluminum,and an artificial foot 17. As can be seen in FIG. 1, the pylon 14includes a vacuum actuator button 16 used to actuate an electric vacuumpump within the pylon that draws air from the socket 12 and, as aresult, draws the residual limb into intimate contact with the interiorof the socket 12.

FIG. 2 illustrates the prosthesis of FIG. 1 in a disassembled state toshow the component parts within the pylon 14. Internal to the pylon 14is a power source 20, such as a capacitor or a conventional 9-voltbattery, a vacuum pump 22, and electrical lines 24 for deliveringelectrical power from power source 20 to vacuum pump 22, and vacuum line26 for drawing vacuum from socket 12 through a check valve 27. The powersource 20, vacuum pump 22, electrical lines 24, vacuum line 26 and checkvalve 27 components are inserted into the pylon 14 after insertion of aribbon 28, so that the ribbon 28 may be subsequently used to extract thecomponents (e.g., for changing or recharging the power source 20).

One suitable type of vacuum pump for use in the present invention is themodel VMP 1624 Series of vacuum pumps, available from VirtualIndustries, Inc., 2130 Vector Place, Colorado Springs Colo. A specificmodel that has been found to be particularly suitable for application asshown herein is model 1624-009-S. This family of pumps is capable ofdrawing vacuum up to 18 inches of mercury (−594 millibar), which issufficient for use in a prosthesis. The pump flow rate is as large as1300 mm per minute. The voltage for the specific model identified aboveis 9 volts, permitting use of the pump with a conventional disposable orrechargeable 9-volt battery. A rechargeable 8 volt lithium ion polymerbattery (model LIPBA-300-8, rated at 300 mAh/8 v) available fromOPRA-TECH Engineering in Warren, Ohio may also be used.

Another line of pumps suitable for use in any embodiment of the presentinvention are available from the Oken Seiko Co., Ltd. in Tokyo, Japan.One particular pump model that has shown itself acceptable in thisregard is model S02R6331, which can operate on between 1.5-3.0 volts.Consequently, such a pump may be powered by a small capacitor, 1-2, 1.5v AAA disposable or rechargeable batteries, or any other acceptablestandard batteries.

Therefore, it can be seen that electrically-powered vacuum pumps areavailable having a size and weight that permits their installation on orwithin the pylon 14, a housing, or another component of a prosthesiswithout substantially increasing the effort and drain on the patientusing the prosthesis. Similarly, such pumps can be easily incorporatedinto a portable inflation pump such as is illustrated in FIG. 5 below.

FIG. 3 is a cross-sectional view of the prosthetic device 10illustrating the components of FIG. 2 after insertion into the pylon 14.As can be seen in FIG. 3, the ribbon 28 forms a loop surrounding thepower source 20 and the vacuum pump 22 so that those components may bewithdrawn from the pylon 14 by pulling at the ends 28 a and 28 b ofribbon which extend to the bottom end of pylon. FIG. 3 furtherillustrates the vacuum and electrical circuits formed by the variouscomponents of the prosthetic device 10. Specifically, an electricalcircuit is formed by the electrical connections 24, the positive andnegative contacts of the power source 20 and the positive and negativeterminals of vacuum pump 22. As can be seen, one electrical connectiondirectly connects one terminal of the power source 20 to one terminal ofvacuum pump 22, while further electrical connections connect the otherterminal of the power source to the other terminal of vacuum pump viaelectrical switch 16. Thus, by closing electrical switch 16, electricalpower is supplied to the vacuum pump 22, causing the vacuum pump tooperate and evacuate the socket 12.

A user of a prosthetic device as thus described can readily createelevated vacuum to any level desired, at least to the limits of vacuumthat can be drawn by the vacuum pump 22. No particular vacuum level isrequired or contemplated by this particular embodiment of the presentinvention, as individual patients may have specific preferences andphysical and/or physiological needs that dictate the level of vacuumdrawn. The described exemplary vacuum pumps each have a flow ratesufficient to evacuate a typical socket to the desired vacuum levelwithin about 30 seconds of vacuum pump operation. Some users willrequire very little vacuum within the socket 12, whereas others willdesire a higher level of vacuum and may, therefore, operate the vacuumpump for a longer period of time. For example, certain levels of vacuummay be desirable due to their potential to reduce the risk of ulcerationand improve vascular flow. Furthermore, the amputee may readily re-applyvacuum using the pump as described above as needed.

As can be further seen in FIG. 3, the vacuum line 26 connects the vacuumpump 22 to a vacuum orifice 30 located in the socket 12 so that thesocket may be evacuated by operation of the vacuum pump. As seen in FIG.2, air drawn through the vacuum line 26 in this embodiment of thepresent invention is expelled via an outlet port 22 b on vacuum pump 22into the interior of the pylon 14. Air expelled into the pylon 14 isvented to the atmosphere, as the interior of a typical pylon is notgenerally sealed from the atmosphere.

As can be seen in FIG. 2 and in FIG. 3, the vacuum line 26 includes acheck valve 27 for permitting airflow through the vacuum tube 26 to thevacuum pump 22 but preventing reverse airflow from the vacuum pumpthrough the vacuum tube and into the socket 12. The check-valve 27 maybe a duckbill-valve or another known type of one-way valve.

Referring now to FIG. 4A, use of the inventive prosthetic device 10 inconnection with a patient's residual limb is illustrated in furtherdetail. As seen in FIG. 4A, a patient's residual limb 40, typicallyhaving a liner donned thereon, is inserted into the socket 12, commonlyleaving a cavity 42 filled with air. In an application wherein a linerwithout an outer fabric covering is used, an air wick sheath such as afabric can be used to prevent the urethane or thermoplastic liner fromsealing the vacuum orifice and thus limiting the vacuum to the openingof the orifice only. Use of an air wick sheath over such a liner canallow air to be evacuated over a larger area of the residual limb. Inapplications wherein a fabric covered liner, such as one of the Alpha®family of liners available from The Ohio Willow Wood Company in Mt.Sterling, Ohio is used, the use of an air wick sheath is unnecessary.

With the liner-covered residual limb inserted into the socket 12, thepatient depresses the actuator button 16, activating the vacuum pump 22and causing air from the cavity 42 to be drawn through the vacuum tube26 and the check valve 27 to the vacuum pump 22, whereafter the air isexpelled into the interior of the pylon 14. The resulting vacuum in thecavity 42 draws the residual limb 40 into tight coupling with theinterior of the socket 12, and permits use of the prosthetic device 10for various ambulatory activities. The vacuum induced coupling betweenthe residual limb 40 and the interior of the socket 12 can be bestobserved in FIG. 4B.

Referring now to FIG. 5, an alternative embodiment of the presentinvention is described. In this alternative embodiment, the pylon 14 issimplified by not including therein the vacuum pump 22 or the powersource 20. Rather, the pylon 14 contains only the vacuum line 26 that iscoupled to the interior of the socket 12. The vacuum line 26 connects toa vacuum orifice coupler 50/52, which includes two parts. A first partof the coupler 50/52 is a check valve 50 that permits airflow from thesocket 12 through the vacuum line 26, but blocks reverse airflow fromthe exterior environment into the vacuum line and socket. As shown, thecoupler 50/52 may also include an orifice 52 for receiving a vacuum linefrom an external portable vacuum pump 56.

A portable evacuation device 56 includes its own vacuum line 54 with acoupler 55 on the end thereof for connection to the vacuum orificecoupler 52. The interior of the portable evacuation device 56 includes apower source 60, such as a capacitor or battery, a vacuum pump 62, and acontrol switch 66. The power source 60 is electrically connected to thevacuum pump 62 via electrical connections similar or identical to thosedescribed above with reference to FIGS. 2-4B, and the vacuum line 54 isconnected to the inlet port of the vacuum pump 62. The portableevacuation device can thus be used to draw air from the socket 12 byconnecting the coupler 55 to the coupler 52, then actuating switch 66 toactivate vacuum pump 62 and draw the air through the vacuum line 54.

One advantage of a portable evacuation device as shown in FIG. 5 is thatthe weight of the power source 60 and the vacuum pump 62, althoughminimal, is removed from the prosthesis. Also, a patient with arelatively long residual limb and, therefore, a short pylon 14, may nothave sufficient volume in the pylon to enclose the motor and/or powersource therein as shown in the preceding drawings. Similarly, above-kneeamputees may not have enough room to incorporate a vacuum system betweena prosthetic knee coupler and the end of the user's socket. In suchcases, a portable evacuation device may be utilized to provide aportable vacuum source for the amputee.

Another embodiment of the present invention is illustrated in FIG. 6. Inthis embodiment, a vacuum pump and power source are again installed to apylon. The vacuum pump, power source and pylon may be the vacuum pump22, power source 20 and pylon 14 shown in FIGS. 2-4B, for example, ormay be entirely different components.

Unlike the installation shown in FIGS. 2-4B, this embodiment of thepresent invention makes use of a special sleeve 68 into which the vacuumpump 22 and power source 20 are installed prior to insertion into thepylon 14. Preferably, the sleeve 68 is formed from a thin andlightweight material that may substantially conform to the shape of thepylon interior. As shown, the sleeve 68 consists of a thin plastic tube,although the use of other materials is certainly also possible. One orboth ends of the sleeve 68 may be open, or the end(s) may be closed butfor small access openings required for vacuum lines or electricalwiring.

The vacuum pump 22 and power source 20 may be retained within the sleeve68 simply by a tight fit between the components and the interior of thesleeve. In an alternate embodiment of the sleeve (not shown), the sleeveinterior may be provided with a special geometry designed to mate withand retain the vacuum pump 22 and/or power source 20.

With the vacuum pump 22 and power source 20 installed in the sleeve 68,the housing is inserted into the pylon as shown in FIG. 6. Retention ofthe sleeve 68 within the pylon 14 can be achieved by a tight fit betweenthe sleeve and the pylon interior or, preferably, a retention means maybe provided. Such a retention means may take many forms such as, forexample, a pin, fastener, tab or other retainer that releasably affixesthe sleeve 68 to the pylon 14. Various types of releasable adhesive,such as one or more pieces of double-stick tape or Velcro® may also beused for this purpose. As shown in FIG. 6, however, retention of thesleeve 68 is accomplished by means of a detent 70. More specifically,when the sleeve 68 is properly inserted into the pylon 14, a projection72 located on the exterior of the housing engages a hole or aperture 74provided in the wall of the pylon. The interaction between theprojection 72 and the aperture 74 is sufficient to retain the sleeve 68during normal use of an associated prosthesis, while also allowing fordisengagement and deliberate removal of the sleeve if desired. Thesleeve 68 may be used in any embodiment of the present invention whereina vacuum pump and power source are installed within a pylon or otherhollow prosthetic component.

Another embodiment of the present invention is shown in FIGS. 7-12. Inthis embodiment, a prosthetic limb 76 includes an evacuation device 80having at least a vacuum pump 84 and power source 86 located in ahousing 82 that is specially designed to mate with a universal distaladapter 88 that is affixed to or integrated into a prosthetic socket 78.Such a distal adapter 88 is shown to be substantially located in thedistal end of the prosthetic socket 78 in FIGS. 8-12, and may employ thefour-hole attachment pattern common to the prosthetics industry.

A proximal (mounting) face 88 a of the distal adapter 88 that residesinterior to the socket 78 is preferably, but not necessarily, concave,to better receive the distal end of the residual limb. The distaladapter 88 also has an aperture 90 passing axially therethrough. Theaperture 90 allows for the passage of various suspension components suchas, for example, locking pins and lanyards, and also receives a portionof the evacuation device housing 82 when the evacuation device 80 isused. Suspension devices associated with such suspension components canbe designed to mate with the distal adapter 88 in the same manner as theevacuation device 80, and theses devices may be made to beinterchangeable.

At least in the embodiment shown, wherein a suction seal is desired, thedistal adapter 88 is optionally, but not necessarily, equipped with oneor more O-rings 92 or similar sealing elements that traverse itsperiphery and assist with providing an air-tight seal between the outersurface of the distal adapter 88 and the interior of the socket 78.Other sealing means may also be employed.

As can be best observed in FIG. 10B, a number of mounting projections94, each having a flat mounting surface 96, extend downward from abottom (connecting) face 88 b of this distal adapter 88 and are exposedalong the bottom of the distal end 78 b of the socket 78. This can beachieved during lamination of the socket 78 by employing a temporarycover plate to protect the mounting surfaces 96 and the aperture 90,while simultaneously allowing socket material to fill the channelsformed between the mounting projections 94. The end result of thistechnique is a substantially flat mounting area at the distal end 78 bof the socket 78, with an aperture that connects the interior of thesocket to the atmosphere via the aperture 90 in the distal adapter 88.In other embodiments, a distal adapter having a single uniform mountingsurface that is exposed along the distal end 78 b of the socket 78 mayalternatively be used in place of an adapter having mountingprojections.

In this particular embodiment, each mounting surface 96 has a threadedmounting hole 98 for receiving a like-threaded fastener. The mountingsurfaces 96 mate with the proximal (mounting) side 82 a of theevacuation device housing 82 when the evacuation device 80 is affixed tothe distal end of the socket 78. As shown, the housing 82 has a numberof thru-holes 100 that are arranged to align with the mounting holes 98located in the mounting surfaces 96 of the distal adapter 88. Fastenersmay be passed through the thru-holes 100 in the housing 82 and threadedinto the distal adapter mounting holes 98 to secure the evacuationdevice 80 to the distal end of the socket 78.

Various prosthetic components may be affixed to the distal (connecting)side 82 b of the evacuation device housing 82 by the same fasteners.These prosthetic components may include, for example, pyramid adapters,Symes adapters, prosthetic ankles, prosthetic feet, prosthetic knees,and other components forming the remainder of a prosthesis.

In the embodiment shown, a sealing extension 102 projects upward fromthe mounting face 82 a of the evacuation device housing 82 through theaperture 90 in the distal end 78 b of the socket 78 and into theaperture 90 in the distal adapter 88. The sealing extension 102preferably carries an o-ring 104 that acts to seal the aperture 90 inthe distal adapter 88.

With the above-described construction, the distal end 78 b of the socket78 is made air tight. As such, mating vacuum passages 106, 108 extendthrough the distal adapter 88 and the distal end 78 b of the socket 78.The vacuum passage 108 in the socket 78 may be created during laminationby means of a projection on the cover plate used to expose the mountingfaces 96 of the mounting projections 94. Alternatively, the vacuumpassage 108 may be bored through the distal end 78 b of the socket 78after lamination thereof. The interface of the vacuum passages 106, 108may be further sealed with an o-ring 110 if desired. Such an o-ring 110may be installed into a recess or counterbore 112 in the distal adapter88.

In this particular embodiment, an evacuation device vacuum passage 114extends from the vacuum pump 84 through the mounting surface 82 a of theevacuation device housing 82. The evacuation device vacuum passage 114is aligned and mates with the vacuum passages 108, 106 in the socket 108and distal adapter 106 when the evacuation device 80 is properly mountedto the distal end 78 b of the socket 78. An o-ring 116 or similarsealing element may be located in the mounting face 82 a of theevacuation device housing 82 and around the evacuation device vacuumpassage 114 to ensure a good seal. The connected vacuum passages 106,108, 114 essentially form one continuous vacuum passageway 118 thatallows the vacuum pump 84 of the evacuation device 80 to evacuate airfrom the interior of the socket 78. A one way valve may be placed in anyof the vacuum passages 106, 108, 114 to ensure that air cannot flow intothe socket 78.

Air evacuated from the socket may be discharged by the vacuum pump 84through an exhaust port 120. The exhaust port 120 may reside at variouslocations in the housing 82. The evacuated air may be dischargeddirectly to the atmosphere, or into another prosthetic component, suchas a pylon, where it can thereafter leak to the atmosphere. A one-wayvalve and/or muffler can be associated with the exhaust port 120.

In an alternate, but similar embodiment of the present invention, anevacuation device vacuum passage may pass from a vacuum pump through thesealing extension 102—instead of through the mounting face 82 a of thehousing 82. In this case, communication with the socket interior occursthrough the aperture 90 in the distal adapter 88 and, therefore, thedistal adapter vacuum passage 106 and socket vacuum passage 108 can beeliminated or plugged.

In this embodiment of the evacuation device 80, an actuator button 122protrudes through the housing 82 for easy access by the user. Otheractuating means may also be used, some of which are described in moredetail below.

Access to the vacuum pump 84, power source 86 and/or other componentslocated within the evacuation device 80 may be accomplished through oneor more access holes or panels (not shown) located in a side(s) of theevacuation device housing 82. Alternatively, the connecting face 82 b ofthe evacuation device housing 82 may comprise a removable plate 124 thatcan be detached as needed to provide access to the vacuum pump 84, powersource 86, and/or other components located within the evacuation devicehousing 82.

It should be noted that another novel and beneficial feature of thisembodiment of the present invention is the use of the universal distaladapter 88. As mentioned briefly above, such a distal adapter can allowfor the interchangeability of various suspension devices, such as theevacuation device, a pin lock device, or a locking lanyard device. Eachsuch device employs the same hole pattern so as to properly mate withthe distal adapter 88. The aperture 90 in the distal adapter is ofsufficient size to allow the passage of a suspension component (e.g., alocking pin or lanyard), but can also be sealed (as described above)when suction suspension is employed.

Another embodiment of the present invention is illustrated in FIG. 13.In this embodiment, a prosthetic limb 126 includes an evacuation device130 for evacuating a prosthetic socket 128. The evacuation device 130includes a housing 132 containing at least a vacuum pump 134 and powersource 136. The housing 132 is designed to fit around a prosthetic pylon138. As shown, the housing 132 may have two halves that can be fastenedtogether around the pylon 138. In a variation of such an evacuationdevice, a housing may be of substantially one-piece construction havinga passageway therethrough for receiving a pylon. Such a housing may beretained on the pylon through an interference fit, or by a clampingmeans, for example.

Although shown to be substantially rectangular in cross-section in FIG.13, the housing 132 may be contoured. For example, the housing 132 maybe contoured in a similar fashion to a human calf, or some otherappropriate or pleasing shape.

In this embodiment of the present invention, the vacuum pump 134 may beconnected to the interior of the socket 128 by a vacuum line 140 thatruns through the pylon 138—in which case an aperture is provided throughthe pylon for passage of the vacuum line. Alternatively, and as shown,the vacuum line 140 may extend from the vacuum pump 134, through thehousing 132 and distal end of the socket 128, and into the socketinterior. As yet another alternative, a vacuum line 140 may extend fromthe vacuum pump 134, through the housing 132, and to a manifold (such asthe manifold 290 described in detail below), which manifold provides forcommunication with the socket interior so that air can be drawntherefrom.

An actuator button 146 may extend through the housing for easy access bythe user. Other actuating means may also be, some of which are describedin more detail below.

Air evacuated from the socket may be discharged by the vacuum pump 134through an exhaust port 148. The exhaust port 148 may reside at variouslocations in the housing 132. A one-way valve and/or muffler can beassociated with the exhaust port 148.

Access to the vacuum pump 134, power source 136 and/or other componentslocated within the evacuation device housing 132 may be accomplished byseparating the halves of the evacuation device housing.

Another embodiment of the present invention is shown in FIG. 14A. Inthis embodiment, an evacuation device 154 includes at least a vacuumpump 166 and power source 168 contained within a housing 156 that isattached to a side wall of a socket 152 of a prosthetic limb 150.Preferably, the housing 156 is affixed to a mounting adapter 158 that isbuilt directly into the socket 152, such as during the laminationthereof.

A vacuum passage 160 may extend through the mounting adapter 158 andsocket sidewall, and into to the interior of the socket 152. Air may beevacuated from the socket interior by drawing it through the vacuumpassage 160 using the vacuum pump 166.

Air evacuated from the socket 152 may be discharged by the vacuum pump166 through an exhaust port 170. The exhaust port 170 may reside atvarious locations in the housing 156 or in the mounting adapter 158.When a manifold is used, an exhaust port may be located therein. Aone-way valve and/or muffler can be associated with the exhaust port 170regardless of its location.

A similar but additional embodiment of the present invention can beobserved in FIG. 14B. In this embodiment, a prosthetic limb 172 isprovided with an evacuation device 176 comprised of at least a vacuumpump 182 and power source 184 residing within a housing 180 that isintegral to a side wall of a prosthetic socket 174. The housing 180protrudes form the side wall of the socket 174 and forms a chamber 186within which the vacuum pump 182 and power source 184 are retained. Thehousing 180 may be a separate component that is laminated or otherwisebonded to the socket 174 after the socket is formed. Preferably,however, the housing 180 is formed along with the socket 174.

The vacuum pump 182 and power source 184 may be permanently sealedwithin the chamber 186. Alternatively, a removable interior cover 188may be provided to ensure that the vacuum pump 182, power source 184,and any other associated components remain within the chamber 186, whileallowing access thereto when required.

A vacuum passage 190 or vacuum line may extend into the interior of thesocket 174. When an interior cover 188 is present, the vacuum passage190 or a vacuum line may extend therethrough. Air is evacuated from thesocket interior by the vacuum pump 182 via the vacuum passage 190.

Air evacuated from the socket may be discharged by the vacuum pump 182through an exhaust port 192. The exhaust port 192 may reside at variouslocations in the housing 180. A one-way valve and/or muffler can beassociated with the exhaust port 192.

In a variation of the embodiments shown and described with respect toFIGS. 14A and 14B, a vacuum line may run from the vacuum pump 166, 182,through the housing 156, 180, and to a manifold connected to the socket152, 174, such as, for example, the manifold 290 depicted in FIG. 19.The manifold provides access to the interior of the socket 152, 174,such that air may be drawn therefrom by the vacuum pump 166, 182. In yetanother variation, a vacuum line may run from the vacuum pump 166, 182,through the housing 156, 180, and to a vacuum passage located moreremotely from the evacuation device, such as on the bottom surface ofthe socket.

Another alternative embodiment of the present invention can be seen inFIG. 15. In this embodiment, an evacuation device 196 including at leasta vacuum pump 200 and power source 202 located in a housing 198, ispositioned within an exoskeletal prosthetic device 194. Morespecifically, the housing 198 is located within a cavity 204 between asocket portion 206 and distal end 208 of the exoskeletal prostheticdevice 194. Such an exoskeletal prosthetic device 194 may account for amajority of a prosthetic leg or prosthetic arm, for example.

The evacuation device 196 may be secured within the exoskeletalprosthetic device 194 in any number of ways. For example, when theevacuation device 196 includes a housing 198, straps, clips, tabs,releasable adhesives, Velcro®, and any number of other types ofretainers may be secured to the interior of the exoskeletal prostheticdevice 194 and used to engage and retain the housing. Such retainers canalso be provided to individually secure the vacuum pump 200 and powersource 202 within the exoskeletal prosthetic device 194 in embodimentsof the present invention wherein no evacuation device housing is used.

In a variation of this embodiment, a mounting pad, plate or other suchstructure may be fabricated or otherwise secured within the cavity 204of the exoskeletal prosthetic device 194 to provide an attaching surface210 for the housing. The housing 198 may be secured to the attachingsurface 210 using any of the retainers mentioned above, or by screws,double-sided tape, or any other known means.

A vacuum passage 212 extends into the interior of the socket 206. Avacuum line 214 connects the vacuum pump 200 of the evacuation device196 to the socket interior via the vacuum passage 212. Air is evacuatedfrom the socket interior by the vacuum pump 200 using the vacuum passage212 and vacuum line 214.

Air drawn from the socket interior may be discharged by the vacuum pump200 directly to the atmosphere through an exhaust port 216 in theexoskeletal prosthetic device 194. Alternatively, air evacuated from thesocket interior may be discharged into the cavity 204 in the exoskeletalprosthetic device 194, where it may thereafter leak to the atmospherethrough one or more component interfaces or be released through theexhaust port 216 which, in this case, may be manually or automaticallyactuable. Any exhaust port associated with any variation of thisembodiment of the present invention may include a one-way valve and/ormuffler.

FIG. 16 depicts another embodiment of the present invention, wherein anevacuation device 222 is affixed to a mounting plate 230 that isdesigned to be mounted between adjacent components of a prosthetic limb218. Preferably, the evacuation device 222 includes a housing 224 thatcontains at least a vacuum pump 226 and power source 228, the housingadapted for affixation to an attachment face 232 of the mounting plate230. Alternatively, the vacuum pump 226 and power source 228 may beindividually affixed to the attachment face 232 of the mounting plate230 without a housing.

The mounting plate 230 is preferably L-shaped, such that a mountingportion 234 thereof can be located between adjacent components of theprosthetic limb 218, while the attachment face 232 extends substantiallyparallel to the length of the prosthetic limb. The mounting plate 230may be located between for example, without limitation, a prostheticankle and foot, or a prosthetic socket 220 and a pyramid adapter 236.

A vacuum line 238 may run from the vacuum pump 226, through the housing224, if present, and into a vacuum passage 240 located in the socket 220of the prosthetic limb 218. The vacuum line 238 may run between thevacuum pump 226 and socket 220 completely exterior to the prostheticlimb 218, as shown, or may be routed at least partially within themounting portion 234, a pylon 242, and/or other components of theprosthetic limb. Those portions of the vacuum line 238 that run exteriorto the prosthetic limb 218 are preferably, but not necessarily,releasably secured to neighboring limb components.

In a variation of this embodiment, a vacuum line may run from the vacuumpump 226 (through the housing 224, if present) to a manifold connectedto the socket 220, such as, for example, the manifold 290 depicted inFIG. 19. The manifold provides access to the interior of the socket 220,such that air can be drawn therefrom. When a manifold is used, any ofthe above-described routings of the vacuum line 238 may be employed.

Air evacuated from the socket 220 may be discharged to the atmosphere bythe vacuum pump 226. The evacuated air may be discharged through anexhaust port 244, which may be located in/on the vacuum pump 226, or atvarious locations in the housing 224 (if present). When a manifold isused, an exhaust port may be located therein. A one-way valve and/ormuffler can be associated with the exhaust port, regardless of itslocation.

FIG. 17 shows another embodiment of the present invention wherein anevacuation device 250 is located within a prosthetic foot 246 (which maybe a solid prosthetic foot or a hollow foot covering). For example, theevacuation device 250 may consist of a vacuum pump 254 and associatedpower source 256 that reside within a cavity 248 in the foot 246.Preferably, however, the evacuation device 250 also includes a housing252 that contains the vacuum pump 254 and power source 256 and islocated in the prosthetic foot cavity 248.

A vacuum line 258 may run from the vacuum pump 254, through theprosthetic foot 246, and into a vacuum passage 260 located in the socket262 of the prosthetic limb 264. The vacuum line 258 may run between thevacuum pump 254 and socket 262 completely exterior to the prostheticlimb 264, as shown, or may be routed at least partially within a pylon266 and/or other components of the prosthetic limb. As an example ofthis latter construction, the vacuum line 258 might be routed fromwithin the foot through a prosthetic ankle and pylon, and into thedistal end of the socket. Those portions of the vacuum line 258 that runexterior to the prosthetic limb 264 are preferably, but not necessarily,releasably secured to neighboring limb components.

In a variation of this embodiment, the vacuum line 258 may run from thevacuum pump 254 to a manifold connected to the socket 262, such as, forexample, the manifold 290 depicted in FIG. 19. The manifold providesaccess to the interior of the socket 262, such that air can be drawntherefrom. When a manifold is used, either of the above-describedroutings of the vacuum line 258 may be employed.

Air evacuated from the socket by the vacuum pump 254 may be dischargedto the atmosphere, preferably through an exhaust port 268 located in theprosthetic foot 246. When a manifold is used, an exhaust port may belocated therein. A one-way valve and/or muffler can be associated withthe exhaust port, regardless of its location.

FIG. 18 illustrates another alternative embodiment of the presentinvention, wherein an evacuation device 270 includes a housing 272containing at least a vacuum pump 274 and power source 276, theevacuation device being located on the user's person and provided toevacuate a socket 278 of a prosthetic limb 280.

As shown in FIG. 18, this embodiment of the evacuation device 270 mayclipped or otherwise attached to a user's belt 282. Alternatively, theevacuation device 270 may be placed in a pocket or temporarily attachedto some other piece of a user's attire. The housing 272 may have anattachment mechanism such as a spring-loaded clip integral thereto or,alternatively, the housing may fit into a sleeve or similar holder thatacts to temporarily secure the evacuation device 270 to a user's attire.Such a holder may operate, for example, much like a clip-on cell phoneholder.

A vacuum line 284 may run from the vacuum pump 274, through the housing272, and into a vacuum passage 286 located in the socket 278 of theprosthetic limb 280. The vacuum line 284 may be routed at leastpartially under the user's clothing. Those portions of the vacuum line284 that run exterior to the prosthetic limb 280 are preferably, but notnecessarily, releasably secured to the prosthetic socket 278.

In a variation of this embodiment, the vacuum line 284 may run from thevacuum pump 274 to a manifold connected to the socket 278, such as, forexample, the manifold 290 depicted in FIG. 19. The manifold providesaccess to the interior of the socket 278, such that air can be drawntherefrom.

Air evacuated from the socket 278 by the vacuum pump 274 may bedischarged to the atmosphere, preferably through an exhaust port 288located in the housing 272. When a manifold is used, an exhaust port maybe located therein. A one-way valve and/or muffler can be associatedwith the exhaust port, regardless of its location.

FIG. 19 depicts yet another embodiment of the present invention, whereina manifold 290 is provided to connect a vacuum source 292 to theinterior of a prosthetic socket 294. The vacuum source 292 may be anevacuation device of the present invention, a hand-operated vacuum pump,or some other vacuum device that can be connected to the manifold 290.

In the particular embodiment shown in FIG. 19, the manifold 290 isassociated with and attached to the distal end of the prosthetic socket294. It should be realized, however, that it would also be possible toattach such a manifold to other portions of the prosthetic socket 294,as long as the attached location permits access to the interior portionof the socket that is to be evacuated.

As can be observed, a vacuum passageway 296 extends through the manifold290. One end 298 of the vacuum passageway 296 is adapted to connect withor receive a vacuum line 302 that connects the manifold 290 to thevacuum source 292. The other end 300 of the vacuum passageway 296 isadapted to align with a vacuum passage 304 that extends through thesocket wall. In this embodiment, the vacuum passage 304 extends throughthe distal end of the socket 294, but could be located elsewhere inother embodiments. An o-ring 306 or other sealing element may be locatedat the interface of the vacuum passageway 296 and the vacuum passage 304to help ensure an air-tight seal.

The manifold 290 may be attached to the socket 294 in a number ofdifferent ways. For example, the manifold 290 may be laminated orotherwise bonded to the socket 294. Alternatively, the manifold 290 maybe secured to a mounting plate 308 that has been integrated into thesocket 294. The manifold 290 could also be affixed to the universaldistal adapter 88 shown in FIGS. 8-12.

Using the vacuum source 292, air is drawn from the socket interiorthrough the manifold 290. The evacuated air may be discharged through anexhaust port associated with the vacuum source 292 or from some otherlocation. As described above, a one-way valve and/or muffler can beassociated with the exhaust port, regardless of its location.

As generally illustrated in FIG. 20, a magnetic switch 310 may be usedin place of an actuator button or other vacuum pump actuator thatrequires direct contact by the user. As shown, the magnetic switch 310resides between a power source 312 and a motor of a vacuum pump 314.When actuated, the magnetic switch 310 allows current to flow from thepower source 312 to the motor, activating the vacuum pump 314 andinitiating the evacuation process.

Unlike a protruding pushbutton or switch, however, actuation of themagnetic switch 310 can often take place through the material forming,for example, an evacuation device housing (see above), a prostheticsocket 316, or a prosthetic pylon 318 (as shown). More specifically, inmany embodiments of the present invention, a user can activate anddeactivate the evacuation device simply by holding a small magneticactivator 320 in close proximity to the magnetic switch 310. Magneticattraction between the magnetic activator 320 and the magnetic switch310 either activates or deactivates the evacuation device as desired.Selective activation and deactivation can be accomplished, for example,by reversing the field of the magnetic activator 320 or by changing thelocation thereof with respect to the magnetic switch 310.

As mentioned previously, a vacuum pump of the present invention may beoperated by various power sources, such as one or more batteries orcapacitors. As one of the main detractions to the use of electronicdevices in prosthetics is the need to eventually replace the powersource, however, evacuation devices of the present invention arepreferably provided with easy access to the power source(s) and/or, morepreferably, employ a rechargeable power source(s).

When employing a rechargeable power source, recharging can beaccomplished by either direct or inductive charging. In the mostsimplistic form of direct charging, the power source is connected to aplug-in charger that transfers electrical energy to the power sourceusing the electrical circuitry of the evacuation device. For example, anevacuation device may have a housing that includes a charging jack thatis connected to the contacts of the power source. The power source ofsuch an embodiment can then be recharged simply by plugging an externalcharger into the charging jack.

Ideally, it is desirable for the user of an evacuation device of thepresent invention to never have to worry about charging of the powersource. That is, even when a simplistic means for direct charging isprovided, a user would still have to monitor or otherwise be informed ofthe charge status of the power source, and act accordingly if the chargelevel reaches a sufficiently low level.

To eliminate this requirement, it is possible to provide an evacuationdevice of the present invention with self-charging capabilities. Forexample, a small inductive generator may be located on the prostheticlimb and placed in electrical communication with the evacuation devicepower source. Such a generator may be constructed and located on theprosthetic limb such that movement of the prosthetic limb duringambulation of the amputee will generate electric power by causingrelative motion of coils within a magnetic field. Electrical energyproduced by the generator is then provided to the evacuation devicepower source to maintain the power source in an acceptably chargedstate.

Other types of electric power generators may be employed for the samepurpose. For example, an electro active polymer (EAP) generator could beassociated with the prosthetic limb. EAP materials have evolved into avery viable alternative to other energy generation methods, and althoughEAP generators do have some limitations, these limitations are notinsurmountable in a prosthetic device application. Alternatively,sufficient charging energy could also be generated using piezoelectricelement generators. Piezoelectric elements generate a voltage inresponse to applied mechanical stress and, therefore, can be caused togenerate electrical energy by movement of a prosthetic limb to whichthey are attached.

Consequently, any evacuation device embodiment of the present inventioncan be provided with such self-charging capability. When so equipped, anevacuation device of the present invention also includes any electricalcircuitry necessary to receive electrical energy from the generator(s),and may also include circuitry and/or other elements to preventover-charging of the power source(s).

With respect to the operational aspects of the evacuation devices of thepresent invention, each embodiment may include basic through advancedversions thereof. More particularly, each embodiment of an evacuationdevice of the present invention may include a basic version thatprovides for manual operation only, an advanced version that is fullyautomatic, and one or more versions having operational features thatfall somewhere therebetween.

At the basic level, each embodiment of an evacuation device of thepresent invention can provide for manual operation. Manual operationessentially involves a user engaging an actuator that results inactivation of a vacuum pump and evacuation of the prosthetic socket. Thevacuum pump will continue to evacuate the socket until the user releasesthe actuator or the vacuum level reaches the maximum level that can beachieved by the pump. Thus, manual operation allows a user to select avacuum level that best corresponds to his/her current activity level ordesired comfort level. Vacuum can be periodically increased or decreasedas desired by the user.

Each embodiment of an evacuation device of the present invention mayalso operate in a semi-automatic mode. This can be achieved by addingcertain types of sensors to the vacuum system, thereby requiring onlyminimal user interaction. For example, in a simplistic embodiment ofsemi-automatic operation, a pressure switch may be provided and simplyconfigured to prevent the vacuum level from exceeding some levelpreviously found to be uncomfortable or otherwise inappropriate for theuser.

In another particular embodiment of semi-automatic operation, a vacuumpump is preset to draw a particular level of vacuum once activated.Therefore, the single intermittent push of a push-button or otheractuator will cause the vacuum pump to operate until an associatedpressure sensor determines that the desired pressure has been met. It isalso possible to mix modes of operation by allowing the user to enter asemi-automatic mode with a quick contact of the actuator, but to enter amanual mode by prolonged contact with the actuator.

Operation of an evacuation device of the present invention can befurther enhanced by adding either logic or a microprocessor. With suchan addition, it is possible to monitor socket pressure and automaticallymaintain the socket pressure within a patient or practitioner definedrange of acceptable pressures. This automatic mode of operationcompletely eliminates the need for the user to monitor the socketpressure, and the prosthetic limb then becomes a device that can simplybe donned and forgotten until removal thereof is desired. It can beappreciated that such a vacuum suspension system will be able toautomatically react to conditions within the socket in a mannerappropriate for the user, and in ways not possible for a mechanical pumpdesign.

The addition of sensors and a microprocessor to an evacuation device ofthe present invention and/or to a prosthetic limb equipped with such anevacuation device, permits the monitoring of various conditions orparameters of the prosthetic limb and/or the user. For example, byappropriately locating a basic pressure transducer in the prostheticsocket, the measuring and tracking of various pressure values associatedwith the prosthetic socket becomes possible. Pressure values of interestmay include maximum or minimum socket pressure, the average pressure inthe socket over some period of time, and the Root Mean Square (RMS)pressure over a defined period of time.

With respect to these latter values, the period of time monitored mightdepend on the conditions that the user or a practitioner is evaluating.For initial setup and function testing, for example, the time periodmight be set to a single step. For evaluation on more complicated taskssuch as engaging in a sport or ascending/descending stairs, the timeperiod might be extended to obtain a target range for all of the variousways that the activity at issue might be performed. The test periodmight even be extended to a period of days to track values for theuser's entire range of activities. Another parameter that may be trackedis some measure of the amount of pressure the user is exposed to overthe course of a period of time. Measure of this parameter would be theintegral of pressure as a function of time, or the integral of thepressure squared as a function of time. With an appropriate link to themicroprocessor, such data can then be displayed on a PC, a key fobdevice, or some other display unit for viewing and analysis by the userand/or practitioner. Of course, the data may also be saved for laterreference.

Because a concern with any vacuum-based prosthetic suspension system isthe quality of the seal, this is another condition that may bemonitored. While it is difficult to directly monitor the seal, it ispossible to monitor the duty cycle of an automatically-controlled vacuumpump motor as the vacuum pump acts to maintain the vacuum level withinthe prosthetic socket. Increases in the duty cycle indicate increases inair leaks and a degradation of the seal. To properly monitor thiscondition, a base line vacuum pump duty cycle can be obtained duringsetup of the associated prosthesis. Monitoring the duty cycle andcomparing it to this baseline will then provide a measure of the sealand allow its quality to be monitored.

Another mode of monitoring the prosthetic socket is a high speed realtime mode. In this mode, vacuum level variations within the socket canbe monitored in real time, as they occur. Data is then recorded relativeto a known time base and allows vacuum fluctuations to be ascribed tospecific events during the user's activities. This mode also allowsgraphical displays to be constructed that can be used to visualize therelationship between a user's activities and the vacuum level within thesocket.

In microprocessor-equipped embodiments of the present invention whereinvacuum level within the socket is or can be monitored, it is alsopossible to monitor the range or variation of the vacuum level and makesome judgments as to the user's activity level based thereon. In thismanner, it is possible to then automatically adjust the level of vacuumto the level of activity of the user. For example, the vacuum level maybe increased over the typical level for a user who becomes very active.Similarly, vacuum level may be automatically decreased if a user issubstantially sedentary or non-ambulatory for some period of time, andthen may be automatically increased when the user becomes more active.This method of monitoring the level of user activity and automaticallyadjusting the vacuum to a correlating level results in a system thatcontinually attempts to keep the vacuum level in the socket at anappropriate level.

As would be understood to one skilled in the art, different phases of anamputee's gait cycle subject the socket of a prosthetic leg to differentstresses, strains, accelerations, and impacts (this is similarly trueduring use of a prosthetic arm). The result is that during differentphases of the gait cycle, the pressure in the socket and the sensationsthat the amputee experiences differ. For example, a level of vibrationthat would be noticeable during the free swing phase of gait, wherevibrations are at a minimum, may not be noticeable if it occurs at thepoint of heel strike where other masking sensations are present.

Also, drawing a vacuum during the free swing phase of the gait cycle ismore difficult to achieve and requires more electrical energy than doesdrawing a vacuum during the stance phase of the gait cycle. This is dueprimarily to the fact that the socket is in tension during the swingphase, while during the stance phase the socket is being driven backonto the amputee's residual limb—thereby effectively forcing air fromthe socket. For at least these of reasons, it is advantageous to monitora lower limb amputee's gait cycle. Movement of the upper limb of anupper extremity amputee can be similarly monitored. Simple tracking canbe achieved by observing the pressure fluctuations in the socket andreacting thereto. When more reliable gait or other movementsynchronization is desired, more complex evaluations can be achievedthrough the addition of accelerometers, gyroscopes, force sensors, orsome combination thereof.

The use of a pushbutton, magnetic switch, and other simplistic actuatorshas been described above with respect to manually operable evacuationdevice embodiments of the present invention. However, other forms ofevacuation device interfaces may also be used, whether in conjunctionwith such actuators or in place thereof.

In one very simplistic information-only interface, basic power,pressure, and functional information can be communicated to the userthrough simple LED indicators. Such an interface may continually displayinformation, or it may display information only when the patientrequests it in order to conserve power. Such a display can be built intothe evacuation device housing, if present.

In another information-only interface, basic information regardingevacuation device function, etc., can be communicated to the user bymeans of an audio transducer. One benefit of this design is that it doesnot require the user to view the evacuation device or some other displayunit associated therewith.

Pushbuttons (and similar switch-type devices) may be used in a verybasic operating and/or programming interface. Pushbuttons are simple,easy to understand, and draw no power when they are not active. Usedwith a properly designed low-power microprocessor, pushbuttons accountfor very little power consumption. There are a number of types ofswitches or switch-type devices that could actually be used. Standardcontact switches are one choice. Membrane-type switches may be areliable, attractive, and space efficient alternative. Also, proximityor capacitive detection switches have recently become available that areable to detect “touches” through a closed container and, as such, wouldeliminate the need for a passage from the outside of an evacuationdevice housing or prosthetic component to the inside. Anotherpossibility is a Hall-type device that operates by using some sort ofmagnetic key. Such a device might be used to provide simple on/offcontrol, perhaps as a backup to other more advanced interfaces.

More complex interfaces may be associated with more complex evacuationdevices of the present invention, such as the semi-automatic andautomatic versions described above. One such interface may be comprisedof a series of pushbuttons associated with the evacuation. Thesepushbuttons may be located, for example, on an evacuation devicehousing. The disadvantage to such an interface, however, is that itrequires the patient to remove clothing, or possibly cosmetic fittings,to activate the vacuum pump, update a program, or make changes to thevacuum settings.

A more convenient method of interfacing with an advanced evacuationdevice of the present invention is through a wireless link. Thus, anevacuation device of the present invention may include a radio, cellularor some other form of wireless transmitter/receiver. A wireless linkwith the transmitter may then be established in any of several ways.

In one embodiment, a stand-alone communication device is used tocommunicate with the evacuation device. Such a stand-alone communicationdevice may be embodied in a key fob, which may include, for example, anintegrated transmitter/receiver, input keys, and an alphanumeric and/orgraphical display. This design would allow a user to keep the key fob intheir pocket and to communicate with the evacuation device easily andinconspicuously. This also allows the user to observe actual operatingconditions and parameters associated with the evacuation device and/orprosthesis, and to optimize evacuation device operation to best suittheir needs.

In another embodiment, a transmitter/receiver may be integrated into acommunication device having a computer compatible interface, such as aserial or USB interface. This design would allow the use of a computer's(e.g., a PC, laptop, pen computer, PDA, etc.) display and computationalcapabilities. More particularly, the communication device could beconnected to a computer and thereafter used to wirelessly communicatewith the evacuation device. This would be especially useful to apractitioner, who could then easily observe variations in a user'ssocket pressure through a step, and from step to step, so as to evaluatethe function of the evacuation device. A practitioner could also adjustthe evacuation device settings, and then save the settings to a harddisk or other storage medium.

Obviously, these are just a few examples of the types of wirelesscommunication devices that may be used in conjunction with an evacuationdevice of the present invention. Such wireless communication devicescould also be used to interact with an evacuation device in more complexways, such as in troubleshooting and programming, for example. It isintended that all interactions capable of being performed locally couldalso be performed using a wireless link.

It can be understood that in versions of the present invention whereinan evacuation device is not provided with self-charging capabilities, orwherein a user wearing a prosthetic limb having a self-charging capableevacuation device is non-ambulatory for an extended period of time, itis possible to discharge the power source(s) to an unacceptable level.As such, it is desirable that an evacuation device of the presentinvention be equipped with a means to notify the user of a low powerstate and/or to take action(s) directed to preserving the powerremaining in the power source.

One method of alerting a user to a low power state is by cycling thevacuum pump. That is, by repeatedly turning the vacuum pump on and offduring the evacuation process, additional vibration and noise will begenerated. While such cycling is unlikely to appreciably decrease theamount of power consumed, the additional vibration and noise can serveas a cue to the user that there is a problem. A user may be similarlyalerted to a low power situation by running the vacuum pump motor at ahigher speed than normal. This would increase motor and/or vacuum pumpnoise, helping to alert the user is aware to the low power situation.

Upon detection of a low power state, a reduction in power consumptioncan be achieved in several ways. First, reducing the required vacuumlevel can be practiced. This method may be employed directly by a userwith a manually operable evacuation device, or automatically by amicroprocessor controlled device. An automatic reduction in vacuum levelmay also serve to notify the user of a low power situation.

With respect to evacuation devices of the present invention where suchare present, the wireless (radio) link may be disabled once a low powerstate is detected. Although minimal, such a radio link does draw somepower from the power source when enabled. Disabling the radio link wouldalso force the user to manually activate the evacuation device, thusmaking the low power state very apparent.

Yet another method of conserving electric power would be to disable theautomatic control system, if present. This would prevent the possiblyfrequent cycling of the evacuation device, especially if the user'sactivity level is increasing. This action would also force the user tointeract with the evacuation device in an alternate fashion that wouldmake the low power condition apparent. Disabling the automatic controlsystem could also allow a user to temporarily disable the evacuationdevice if the user's current activity level does not necessitate suctionsuspension—thereby preserving power to adjust the vacuum level shouldthe user's activity level change.

Other means of alerting a user to a low power condition are certainlyalso possible. For example, a visual and/or audible alert may beemployed, such as through the use of the LED or audio transducerinterfaces described above.

As mentioned previously, sensors, a microprocessor, and other devicesmay be associated with an evacuation device to form a more advancedprosthetic evacuation system. Such systems may provide for a number ofoperational modes that offer various advantages in function,convenience, and privacy.

One such operational mode is a multi-speed vacuum mode. At lower levelsof power consumption, the vacuum pump motor operates at a reduced levelof performance, but also at a reduced noise level. Therefore, in thismulti-speed vacuum mode of operation, the user may choose between one ofseveral predetermined levels of vacuum pump performance—with lowerperformance levels producing less noise and higher performance levelsproducing more noise. Thus, for example, if the user is in a noisesensitive environment (e.g., the theater, a library, etc.) and theiractivity level is relatively low, the user may choose a lowerperformance level to minimize noise. If noise is of little or noconcern, then the user might select a higher performance level.

In addition to vacuum pump performance level selection by the user,another way to take advantage of the multi-speed vacuum mode ofoperation would be to use a level of activity monitor, as describedabove. Such a level of activity monitor could be used to detect thelevel of activity of the user and to subsequently adjust the performanceof the vacuum pump to an appropriate level. This would have theadditional advantage of reducing power consumption when the user issubstantially sedentary.

An evacuation device of the present invention may also be used to assistwith doffing (removal) of the prosthesis to which it is installed. Whenremoval is desired, the user first typically removes a sealing sleeve,if present, and subsequently releases the vacuum in the socket by eitherplacing a tool therein to open a passageway along the socket interior orby opening or otherwise activating an air valve. With the vacuumreleased, the prosthesis can then be removed from the residual limb. Toassist with the removal process, an evacuation device of the presentinvention may employ a reversible vacuum pump to pump air back into thedistal end of the socket and encourage its dislodgement from theresidual limb. Alternatively, an evacuation device of the presentinvention may use two pumps; one to evacuate the socket during donningof a prosthesis and one to pressurize the socket during doffing of theprosthesis.

In addition to simply evacuating a prosthetic socket to impart suctionsuspension to a prosthesis, an evacuation device of the presentinvention can also have therapeutic uses. Amputees are often the victimsof chronic wounds that seemingly will not heal. These wounds aresometimes the result of operations, and sometimes result from pressuresores. One of the dilemmas frequently faced by amputees is how to lettheir stump heal when its use is often necessary to their dailyactivities. While this dilemma is not unique to upper or lower limbamputees, it may be more problematic for lower limb amputees becausethey must rely on their residual limbs for ambulation and because theirresidual limbs are generally subjected to more forces and pressures thanare those of upper limb amputees.

Research since about 1993 has indicated that sub-atmospheric pressurecan be of benefit to the healing of chronic wounds. Blood flow has beenfound to be augmented by treatment at reduced pressures of around 125mmHg. Healing has been shown to be further improved by cycling thereduced pressure; such as by repeatedly applying vacuum forapproximately 5 minutes, removing the vacuum for 2 minutes, andrepeating.

An evacuation device of the present invention can be used with asealable socket to provide such a vacuum therapy regimen. The socket maybe for treatment use only and may be disposable to obviate any concernsrelating to the seepage of wound fluids during treatment. Such a socketmay be especially useful for the treatment of new amputees.Alternatively, the socket may be part of a prosthesis. When incorporatedinto the stump socket of a prosthesis, the evacuation device may beprogrammed to enter a therapy mode when the amputee is inactive. Thismay be useful when the amputee has a wound(s) or other condition(s) thatwill benefit from vacuum therapy.

In this embodiment of the present invention, the evacuation device isprogrammed or otherwise set to achieve the desired vacuum level whenoperated. The evacuation device is further programmed to cycle on andoff in order to repeatedly apply and release the vacuum, and to maintainthe vacuum level for the necessary time—whatever that time is determinedto be.

In conjunction with the above discussion, it is worth noting that one ofthe primary causes of sores on a residual limb is excessive motion ofthe residual limb within a prosthetic socket. An evacuated socket helpsto maintain residual limb volume, thereby greatly reducing the tendencyof the residual limb to move within a prosthetic socket. However, it isdifficult to know what level of vacuum is actually necessary for a givenpatient at a given activity level, on a specific day. To help make sucha determination, a residual limb motion sensor can be integrated into aprosthetic socket, and used to adjust the vacuum level therein. Ifmotion over some period of time is too high, more vacuum is drawn. Ifthe vacuum level has been maintained, but the user's activity level hasdeclined, the vacuum level can be slowly reduced until motion isdetected. The vacuum level can then be increased as necessary until themotion ends or is maintained at a level for which the current vacuumlevel is appropriate. Over time, a map of activity level vs. pressure(vacuum level) can be constructed and referenced to allow for quickervacuum adjustments.

Several types of sensors can acceptably serve as the motion sensordescribed above. For example, the motion sensor may be comprised of aHall sensor placed in the base of a prosthetic socket and a small magnetfastened to the tip of a prosthetic liner worn over the residual limb.Alternatively, the motion sensor may be comprised of a mutual inductancedevice that measures the mutual inductance between a coil in the base ofa prosthetic socket, and a small coil placed on the tip of a prostheticliner worn over the residual limb. In another embodiment, the motionsensor may be comprised of an ultrasonic sensor that is tuned to detecta small metal plate mounted on the tip of a prosthetic liner worn overthe residual limb. Placing this sensor in the prosthetic socket coulddirectly detect a residual limb or prosthetic liner. In yet anotherembodiment, the motion sensor may be comprised of a force sensor placedin the bottom of a prosthetic socket. Intermittent contact of theresidual limb with the force sensor will indicate the occurrence ofresidual limb motion within the socket.

While various embodiments of the present invention have been illustratedprimarily with respect to the case of lower limb prostheses, the presentinvention also applies to upper limb prostheses. Additional advantagesand modifications will readily appear to those skilled in the art andare considered to be within the scope of the present invention.

Therefore, while certain embodiments of the present invention aredescribed in detail above, the scope of the invention is not to beconsidered limited by such disclosure, and modifications are possiblewithout departing from the spirit of the invention as evidenced by thefollowing claims:

1. A prosthetic device, comprising: a socket for receiving a residuallimb; a vacuum passageway for evacuation of air from said socket; and anevacuation device comprising an electrically powered vacuum pump and asource of electric power located within a housing that is adapted forattachment to said socket, said vacuum pump in communication with saidvacuum passageway; wherein said vacuum pump is activated to evacuatesaid socket by drawing air therefrom while said residual limb is locatedwithin said socket.
 2. The prosthetic device of claim 1, furthercomprising an adapter associated with said socket and located at adistal end thereof.
 3. The prosthetic device of claim 2, wherein saidadapter is an integral part of said socket.
 4. The prosthetic device ofclaim 2, wherein a vacuum passage in said adapter and a vacuum passagein said socket cooperate to form said vacuum passageway.
 5. Theprosthetic device of claim 2, further comprising a vacuum passage insaid housing, said vacuum passage connected to said vacuum pump andlocated to align with said vacuum passageway when said evacuation deviceis properly installed to said adapter.
 6. The prosthetic device of claim2, further comprising an o-ring between said vacuum passage in saidadapter and said vacuum passage in said socket.
 7. The prosthetic deviceof claim 2, wherein said evacuation device is attached to said adapterby passing a number of threaded fasteners through receiving holes insaid housing and threading said fasteners into like-threaded mountingholes in said adapter.
 8. The prosthetic device of claim 7, wherein eachmounting hole resides in a corresponding adapter mounting surface thatis exposed along a bottom of said socket.
 9. The prosthetic device ofclaim 2, wherein said adapter includes an axial aperture for allowingpassage therethrough of various prosthetic suspension components. 10.The prosthetic device of claim 1, wherein said housing is furtheradapted for connection to one of a plurality of prosthetic connectingadapters.
 11. The prosthetic device of claim 10, wherein said prostheticconnecting adapter is a pyramid adapter.
 12. The prosthetic device ofclaim 1, further comprising an exhaust port in said housing throughwhich evacuated air is exhausted.
 13. The prosthetic device of claim 12,further comprising a one-way valve and/or muffler associated with saidexhaust port.
 14. The prosthetic device of claim 1, further comprisingan actuator extending through said housing for allowing a user toactivate said vacuum pump by continued contact with said actuator. 15.The prosthetic device of claim 1, further comprising a magnetic switchbetween said power source and said vacuum pump, said magnetic switchallowing for remote activation of said vacuum pump.
 16. The prostheticdevice of claim 1, further comprising one or more sensors and amicroprocessor in communication with said evacuation device.
 17. Theprosthetic device of claim 16, wherein at least one sensor is a vacuumlevel sensor that monitors vacuum level within said socket.
 18. Theprosthetic device of claim 17, wherein said microprocessor uses inputfrom said vacuum level sensor to operate said vacuum pump such that saidsocket is automatically evacuated to some predetermined level once saidvacuum pump is initially activated by a user.
 19. The prosthetic deviceof claim 17, wherein said microprocessor uses said vacuum level sensorto continually monitor vacuum level within said socket and automaticallyoperates said vacuum pump as necessary to maintain said socket at somepredetermined vacuum level.
 20. The prosthetic device of claim 17,wherein said microprocessor uses said vacuum level sensor to monitorvacuum level within said socket and operates said vacuum pump asnecessary to automatically adjust said vacuum level to correspond tochanges in a user's activity level.
 21. The prosthetic device of claim1, further comprising a means of indicating a low power condition to auser.
 22. The prosthetic device of claim 1, wherein said vacuum pump isreversible to pressurize said socket during doffing of an associatedprosthetic limb.
 23. The prosthetic device of claim 1, furthercomprising a second vacuum pump to pressurize said socket during doffingof an associated prosthetic limb.
 24. The prosthetic device of claim 1,further comprising a wireless receiver/transmitter associated with saidevacuation device for allowing wireless communication therewith.
 25. Theprosthetic device of claim 1, wherein said power source is rechargeable.26. The prosthetic device of claim 25, further comprising a generatormounted to a prosthetic limb with which said prosthetic device is used,said generator recharging said power source with electrical energyautomatically produced by said generator as a result of movement of saidprosthetic limb.
 27. The prosthetic device of claim 26, wherein saidgenerator is comprised of an inductance device, a piezoelectric element,or an electroactive polymer.
 28. The prosthetic device of claim 1,wherein said vacuum pump is cycled to repeatedly draw and release avacuum within said socket, thereby providing vacuum therapy to saidresidual limb.
 29. A prosthetic device, comprising: a prosthetic socketfor receiving a residual limb; a universal adapter integrated into adistal end of said socket, said adapter having an axial aperture passingtherethrough for allowing passage of various suspension components; anumber of mounting projections extending from a bottom face of saidadapter, each mounting projection having a mounting surface that isexposed along a bottom surface of said socket; a vacuum passage in saiddistal adapter and a vacuum passage in said socket, said vacuum passagescooperating to form a vacuum passageway for evacuation of air from saidsocket; an evacuation device comprising an electrically powered vacuumpump and a source of electric power contained within a housing that islocated at said distal end of said socket and secured to said mountingsurfaces of said adapter; a vacuum passage in said housing, said vacuumpassage connected to said vacuum pump and located to align with saidvacuum passageway when said evacuation device is properly installed tosaid adapter; wherein said vacuum pump is activated to evacuate saidsocket by drawing air therefrom through said vacuum passageway whilesaid residual limb is located within said socket.
 30. The prostheticdevice of claim 29, wherein said housing is further adapted forconnection to one of a plurality of prosthetic connecting adapters. 31.The prosthetic device of claim 29, wherein said evacuation device isattached to said adapter by passing a number of threaded fastenersthrough receiving holes in said housing and threading said fastenersinto like-threaded mounting holes in said mounting surfaces.
 32. Theprosthetic device of claim 29, further comprising an exhaust port insaid housing through which evacuated air is exhausted.
 33. Theprosthetic device of claim 32, further comprising a one-way valve and/ormuffler associated with said exhaust port.
 34. The prosthetic device ofclaim 29, further comprising an actuator extending through said housingfor allowing a user to activate said vacuum pump by continued contactwith said actuator.
 35. The prosthetic device of claim 29, furthercomprising one or more sensors and a microprocessor in communicationwith said evacuation device.
 36. The prosthetic device of claim 35,wherein at least one sensor is a vacuum level sensor that monitorsvacuum level within said prosthetic socket.
 37. The prosthetic device ofclaim 36, wherein said microprocessor uses input from said vacuum levelsensor to operate said vacuum pump such that said prosthetic socket isautomatically evacuated to some predetermined level once said vacuumpump is initially activated by a user.
 38. The prosthetic device ofclaim 36, wherein said microprocessor uses said vacuum level sensor tocontinually monitor vacuum level within said prosthetic socket andautomatically operates said vacuum pump as necessary to maintain saidprosthetic socket at some predetermined vacuum level.
 39. The prostheticdevice of claim 36, wherein said microprocessor uses said vacuum levelsensor to monitor vacuum level within said prosthetic socket andoperates said vacuum pump as necessary to automatically adjust saidvacuum level to correspond to changes in a user's activity level. 40.The prosthetic device of claim 29, further comprising a means ofindicating a low power condition to a user.
 41. The prosthetic device ofclaim 29, wherein said vacuum pump is reversible to pressurize saidprosthetic socket during doffing of an associated prosthetic limb. 42.The prosthetic device of claim 29, further comprising a second vacuumpump to pressurize said socket during doffing of an associatedprosthetic limb.
 43. The prosthetic device of claim 29, furthercomprising a wireless receiver/transmitter associated with saidevacuation device for allowing wireless communication therewith.
 44. Theprosthetic device of claim 29, wherein said power source isrechargeable.
 45. The prosthetic device of claim 44, further comprisinga generator mounted to a prosthetic limb with which said prostheticdevice is used, said generator recharging said power source withelectrical energy automatically produced by said generator as a resultof movement of said prosthetic limb.
 46. The prosthetic device of claim45, wherein said generator is comprised of an inductance device, apiezoelectric element, or an electroactive polymer.
 47. The prostheticdevice of claim 29, wherein said vacuum pump is cycled to repeatedlydraw and release a vacuum within said socket, thereby providing vacuumtherapy to said residual limb.
 48. A prosthetic limb system, comprising:a prosthetic limb having a prosthetic socket for receiving a residuallimb; a vacuum passageway for evacuation of air from said prostheticsocket; and an evacuation device comprising an electrically poweredvacuum pump and a source of electric power located within a housing thatis adapted for attachment to said prosthetic socket, said vacuum pump incommunication with said vacuum passageway; wherein said vacuum pump isactivated to evacuate said prosthetic socket by drawing air therefromwhile said residual limb is located within said socket.